Coil device, phase shift circuit, and communication apparatus

Abstract

In a coil device, a first coil includes a common terminal side first coil conductor connected to a ground terminal, an intermediate first coil conductor, and an input/output terminal side first coil conductor connected to a first input/output terminal, and a second coil includes a common terminal side second coil conductor connected to the ground terminal, an intermediate second coil conductor, and an input/output terminal side second coil conductor connected to a second input/output terminal. The input/output terminal side first coil conductor is located between the intermediate second coil conductor and the input/output terminal side second coil conductor, and the input/output terminal side second coil conductor is located between the intermediate first coil conductor and the input/output terminal side first coil conductor.

What is claimed is: 
     
       1. A coil device comprising:
 an insulating substrate; and 
 a first input/output terminal, a second input/output terminal, a common terminal, a first coil, and a second coil, each of which is provided on the insulating substrate; wherein 
 the first coil includes a first coil conductor with a shape wound around a first winding axis; 
 the second coil includes a second coil conductor with a shape wound around a second winding axis parallel or substantially parallel to a direction of the first winding axis; 
 the first coil includes a plurality of first coil conductors provided over a plurality of layers, the plurality of first coil conductors including an input/output terminal side first coil conductor with one end connected to an input/output terminal; 
 the second coil includes a plurality of second coil conductors provided over a plurality of layers, the plurality of second coil conductors including an input/output terminal side second coil conductor having one end connected to an input/output terminal; 
 the input/output terminal side first coil conductor is located between two second coil conductors among the plurality of second coil conductors in a direction of the second winding axis, and overlaps the two second coil conductors when viewed in a direction of the second winding axis; 
 one of the two second coil conductors is the input/output terminal side second coil conductor; 
 the input/output terminal side second coil conductor is between two first coil conductors among the plurality of first coil conductors in a direction of the first winding axis, and overlaps the two first coil conductors when viewed in a direction of the first winding axis; and 
 one of the two first coil conductors is the input/output terminal side first coil conductor. 
 
     
     
       2. The coil device according to  claim 1 , wherein
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is a common terminal side first coil conductor with one end connected to the common terminal; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is a common terminal side second coil conductor with one end connected to the common terminal. 
 
     
     
       3. The coil device according to  claim 2 , wherein
 a line width of the input/output terminal side first coil conductor includes a portion thicker than a line width of the common terminal side first coil conductor; and 
 a line width of the input/output terminal side second coil conductor includes a portion thicker than a line width of the common terminal side second coil conductor. 
 
     
     
       4. The coil device according to  claim 2 , wherein
 a number of turns of the input/output terminal side first coil conductor is greater than a number of turns of the common terminal side first coil conductor; and 
 a number of turns of the input/output terminal side second coil conductor is greater than a number of turns of the common terminal side second coil conductor. 
 
     
     
       5. The coil device according to  claim 1 , wherein
 the plurality of first coil conductors include a common terminal side first coil conductor with one end connected to the common terminal, and an intermediate first coil conductor sandwiched between the input/output terminal side first coil conductor and the common terminal side first coil conductor in a direction of the first winding axis; 
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is the intermediate first coil conductor; 
 the plurality of second coil conductors include a common terminal side second coil conductor with one end connected to the common terminal, and an intermediate second coil conductor sandwiched between the input/output terminal side second coil conductor and the common terminal side second coil conductor in a direction of the second winding axis; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is the intermediate second coil conductor. 
 
     
     
       6. The coil device according to  claim 1 , wherein
 a number of turns of the input/output terminal side first coil conductor is greater than 1; 
 an interlayer connection conductor connected to the input/output terminal side first coil conductor is positioned in a coil opening of the input/output terminal side second coil conductor; 
 a number of turns of the input/output terminal side second coil conductor is greater than 1; and 
 an interlayer connection conductor connected to the input/output terminal side second coil conductor is positioned in a coil opening of the input/output terminal side first coil conductor. 
 
     
     
       7. A phase shift circuit comprising:
 the coil device according to  claim 1 ; and 
 a phase shift line connected in series to the coil device and having an amount of phase shift of less than about 90°. 
 
     
     
       8. A communication apparatus comprising:
 a transmission/reception circuit; and 
 an antenna connected to the transmission/reception circuit; wherein 
 the communication apparatus includes the phase shift circuit according to  claim 7  between the transmission/reception circuit and the antenna. 
 
     
     
       9. A communication apparatus comprising:
 a transmission/reception circuit; and 
 a diplexer connected to the transmission/reception circuit; wherein 
 the communication apparatus includes the phase shift circuit according to  claim 7  between the transmission/reception circuit and the diplexer. 
 
     
     
       10. The phase shift circuit according to  claim 7 , wherein
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is a common terminal side first coil conductor with one end connected to the common terminal; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is a common terminal side second coil conductor with one end connected to the common terminal. 
 
     
     
       11. The phase shift circuit according to  claim 10 , wherein
 a line width of the input/output terminal side first coil conductor includes a portion thicker than a line width of the common terminal side first coil conductor; and 
 a line width of the input/output terminal side second coil conductor includes a portion thicker than a line width of the common terminal side second coil conductor. 
 
     
     
       12. The phase shift circuit according to  claim 10 , wherein
 a number of turns of the input/output terminal side first coil conductor is greater than a number of turns of the common terminal side first coil conductor; and 
 a number of turns of the input/output terminal side second coil conductor is greater than a number of turns of the common terminal side second coil conductor. 
 
     
     
       13. The phase shift circuit according to  claim 7 , wherein
 the plurality of first coil conductors include a common terminal side first coil conductor with one end connected to the common terminal, and an intermediate first coil conductor sandwiched between the input/output terminal side first coil conductor and the common terminal side first coil conductor in a direction of the first winding axis; 
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is the intermediate first coil conductor; 
 the plurality of second coil conductors include a common terminal side second coil conductor with one end connected to the common terminal, and an intermediate second coil conductor sandwiched between the input/output terminal side second coil conductor and the common terminal side second coil conductor in a direction of the second winding axis; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is the intermediate second coil conductor. 
 
     
     
       14. The phase shift circuit according to  claim 7 , wherein
 a number of turns of the input/output terminal side first coil conductor is greater than 1; 
 an interlayer connection conductor connected to the input/output terminal side first coil conductor is positioned in a coil opening of the input/output terminal side second coil conductor; 
 a number of turns of the input/output terminal side second coil conductor is greater than 1; and 
 an interlayer connection conductor connected to the input/output terminal side second coil conductor is positioned in a coil opening of the input/output terminal side first coil conductor. 
 
     
     
       15. A communication apparatus comprising:
 a transmission/reception circuit; and 
 an antenna connected to the transmission/reception circuit; wherein 
 the communication apparatus includes the coil device according to  claim 1  between the transmission/reception circuit and the antenna. 
 
     
     
       16. The communication apparatus according to  claim 15 , wherein
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is a common terminal side first coil conductor with one end connected to the common terminal; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is a common terminal side second coil conductor with one end connected to the common terminal. 
 
     
     
       17. The communication apparatus according to  claim 15 , wherein
 the plurality of first coil conductors include a common terminal side first coil conductor with one end connected to the common terminal, and an intermediate first coil conductor sandwiched between the input/output terminal side first coil conductor and the common terminal side first coil conductor in a direction of the first winding axis; 
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is the intermediate first coil conductor; 
 the plurality of second coil conductors include a common terminal side second coil conductor with one end connected to the common terminal, and an intermediate second coil conductor sandwiched between the input/output terminal side second coil conductor and the common terminal side second coil conductor in a direction of the second winding axis; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is the intermediate second coil conductor. 
 
     
     
       18. A communication apparatus comprising:
 a transmission/reception circuit; and 
 a diplexer connected to the transmission/reception circuit; wherein 
 the communication apparatus includes the coil device according to  claim 1  between the transmission/reception circuit and the diplexer. 
 
     
     
       19. The communication apparatus according to  claim 18 , wherein
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is a common terminal side first coil conductor with one end connected to the common terminal; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is a common terminal side second coil conductor with one end connected to the common terminal. 
 
     
     
       20. The communication apparatus according to  claim 18 , wherein
 the plurality of first coil conductors include a common terminal side first coil conductor with one end connected to the common terminal, and an intermediate first coil conductor sandwiched between the input/output terminal side first coil conductor and the common terminal side first coil conductor in a direction of the first winding axis; 
 another one of the two first coil conductors, which is different from the input/output terminal side first coil conductor, is the intermediate first coil conductor; 
 the plurality of second coil conductors include a common terminal side second coil conductor with one end connected to the common terminal, and an intermediate second coil conductor sandwiched between the input/output terminal side second coil conductor and the common terminal side second coil conductor in a direction of the second winding axis; and 
 another one of the two second coil conductors, which is different from the input/output terminal side second coil conductor, is the intermediate second coil conductor.